There is not a set of standard indicators that tell us that we are about to enter a bull market, after all even if you could find a set of indicators that described the start of every single bull run that we have seen you will find that many times those same conditions have presented themselves and yet we did not witnessed a bull market at the time.

So if what you are looking for is for a way to perfectly predict when we are about to enter a bull market then I am sorry to disappoint you as nothing remotely close to it exists at all.